Support the channel by shopping through this link: https://amzn.to/4fatbMb Become a member: https://www.youtube.com/@d4a/join Patreon: https://www.patreon.com/d4a The other day when I opened youtube I was (surprisingly) shown a really interesting short video. It was a video about something I later found out was called a Paillard clockwork fan, which allegedly is a 100% mechanical cooling fan. No batteries, cables or anything else. You give it a winding and allegedly it cools you for 30 minutes. But these fans are ancient, they are from the early 1900s, they’re more than 100 years old, so I decided to look for a modern equivalent of one…..and I found nothing. There is no modern equivalent. Nobody makes this nowadays. All we have are fans that are plugged into the electricity grid or battery-powered. The only manual fans we have need to be continuously squeezed to run and they’re small, weak and your and gets very tired after just a few minutes. And honestly this surprised me because there’s a market for this. Think about it, a lot of people want to live off-grid and electrical motors are very power hungry. There’s also a lot of people who live and/or work in hot remote areas where there’s no electricity. This would also be nice in a power outage because you also have your hands with you, and all you have to do is wind it up once in a while. So I decided to try and build one myself, and if successful, I will offer the files for free. Obviously the first step towards making this is understanding how it works. Fortunately, the original video does give us some useful clues. The first thing we can observe is the geartrain of the fan. The only purpose of which is to increase the output speed. The fan blades themselves are our output and we want it to spin fast enough so that I can move a substantial amount of air quickly in order to cool us down. The question is: what is inside the box below the gear train? Well, this is called a “clockwork fan”, we can hear and see winding and ratchething, and the short video mentioned a spring motor…and that tells me that inside this there must be a mainspring. And I know just the place where I can get one easily and for very little money. In a hardware store from any tape measure. When you think about it mainsprings are the first “battery”, before we learned how to chemically store electrical energy, we learned how to store kinetic or mechanical energy! Sometimes in 15th century Europe somebody came up with the mainspring. It allowed us to store more kinetic energy far more conveniently and in a much smaller space than a hanging weight which was previously the norm. Mainsprings revolutionized our lives because they gave us the ability to take timekeeping devices with us, they made pocket and wrist watches possible. But even mainsprings were kind of inconvenient all the way up to the 1960s. It took us centuries to figure out the right allows and heat-treating processes to create the kind of spring steel that gave mainsprings the kind of yield strength and fatigue life that today we take for granted. A mainspring can be wound and unwound almost an infinite amount of times without loosing it’s shape or breaking. It is very strong and very elastic at the same time. Before the 1960s, mainsprings were the main cause of watch repair simply because they didn’t last as long. Of course you can find mainspring outside of watches and clocks in everything from toys to retractable dog leashes, egg timers and more. Something I did on my model/prototype is that I decreased the gear module from bottom to top. The gear module is simply the tooth size of metric gears. Larger teeth are obviously stronger a nd as such have higher load bearing capacity but are also noisier and less smooth which makes them better suited to low rpm and high torque On the other hand smaller gear teeth obviously have a lower load bearing capacity but are smoother, quieter and more efficient at rpm which aligns perfectly with our application since our torque decreases and speed increases as we go up in the gear train. I have also changed the pressure angle for the last gear pair which will operate at the highest rpm. A 14.5 degree pressure angle is smoother, quieter and overall better suited and more efficient at high rpm. It has poor shock resistance and is easier to strip with high torque, but we won’t really have any shocks or high torque by the time the torque is transferred to the top of the gear train. A special thank you to my patrons: Daniel Peter Della Flora valqk Dave Westwood Zwoa Meda Beda Cole Philips Allan Mackay Sam Lutfi Alex 00:00 Swiss Genius 03:37 To Make it We Need to Know How it Works 04:54 Mainsprings Were The First Batteries 11:54 Capturing a Mainspring 15:47 Fancy and Irrelevant Gear Specs 21:21 Good News and Bad News 25:55 V2.0 28:21 Saving my Shaft 30:07 Winding to Running Ratio #d4a
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The original machine also had a massive 2 inch wide mainspring that was strong enough to need a long crank handle. If your tape measure and plastic gears can make any measurable breeze and run for almost 2 minutes, I bet that one made a decent breeze, ran for quite a while, and would probably remove at least an arm if the casing let loose...
Try using a belt drive. You can print an adapter for the spring barrel and use a small gear on the propeller shaft. This will minimize losses because you can achieve a gear ratio of 16:1 with a single stage transmission.
11:28 ".. by the magic of buying two"
That intro is so real. I open the YouTube app to watch my favorite automotive YouTuber and instead I am instantly served a video whose content I can no longer remember.
Thought this was a Technology Connections video when I saw the Thumbnail 😂 Thanks D4A. Great content 👍
Quick get food, D4A uploaded
The spring you used was maybe only 10% of the strength required, and 16:1 should be closer to 250:1. Notice in the video the spring barely moved -and it was maybe 5 or 6 inches wide. And, yeah, metal gears.
Rather than sanding the faces of the gears, I think I would offset them so that the faces don't touch. Small bosses on the gear shafts press against the inner race of the bearings to keep the gear in place and maintain the clearance between the faces.
0:12 thats why i am using modded app, with shorts, ai summaries, e.t.c, cutted out.
A couple things to consider. The fan blade used I suspect was from a standard AC fan using a 2 pole induction motor. In the US that motor running on 60 Hz AC, it has a theoretical max speed of 3600 RPM. In the EU that motor running on 50 Hz AC, it has a theoretical max speed of 3000 RPM. I believe your mechanism would not come close that that speed. Fan blades with a higher pitch would work better at a lower RPM providing more resistance causing mechanism to run longer. Also the video device appeared to have a higher gear ratio, which should provide greater resistance to the spring, causing a longer run time. I would be interested to see the original device to running on a full winding to see how much air it moves and how long it runs.
You need a much heavier spring , you can tell they where using mechanical advantage and a ratcheting mechanism to store energy in the antique ones.
They once used that exact technology to turn a rotisserie over a fire. It was probably used more for that than a cooling fan.
feel like a sponsored episode from one of those online CNC places might have been in order
how to get a cut 101:
failures are the most useful part of every content, thanks for keeping it
Maybe Lubricant would help it run a bit longer. Silicone Spray or something.
#freeSprings they have feelings and should not be in constant pain!
Alternatively you can buy an old clock mechanism complete with a large drum mainspring and gear train that can easily be adapted to run a fan. I've got a large chiming clock which is still fine after 150+ years, running for 8 days on a single winding and keeping very good time. Apparently they did have the metallurgy some time back... 😏
Ah soon you'll start to see the scam ads for portable AC that cools you for free. Thankfully D4A precedes this with something that actually does that.
The discussion about clocks made me realise how ridiculously important just keeping time more and more accurately has been in advancing technology.